Ground cover mats are used in constructions sites to cover areas of ground and to allow vehicles and heavy machinery to drive over the ground cover mats. Typically, the ground cover mats are placed over pipelines, surface lines (e.g. fluid hoses, power cables, data wires), and other objects that are to be protected. Ground cover mats are also placed over ground surfaces that could be problematic for vehicles and heavy machinery to cross over. For example, soft ground, holes, ditches and streams may be covered by a ground cover mat to enable vehicles or heavy machinery to cross over.
In the pipeline industry, pipelines are buried underneath, laid upon, or supported in a raised position above a ground surface. Because of the distances travelled by such pipelines, and other factors, it is often necessary for a road or passage to cross a pipeline. For buried pipelines, the crossing passes over the pipeline, for example directly or indirectly above fill material above the pipeline. Regulations may determine the minimum depth of fill required between the pipeline and the road in some cases. Regardless, vibration and compression from multiple crossings over time may lead to damage and eventual failure of the buried pipeline. Therefore, ground cover mats may be laid over a pipeline for machinery to cross over.
Ground cover mats are also called swamp mats, rig mats, and pipeline mats. These mats are typically intended to be easy to setup and are temporarily used. Ground cover mats are typically low profile so that less soil or dirt is required to form a ramp leading up to the ground cover mat in order for vehicles or heavy machinery to cross over the ground cover mat. A low profile also makes it easier for vehicles or heavy machinery to traverse over the ground cover mat.
In many cases, ground cover mats are created using planks of wood that are fastened together to form a board. In some cases, oak wood is used to create “oak mats”. These wood mats are easy to assemble on site, but are not durable and may not be able to withstand the loads of the heaving machinery and vehicles. Consequently, the pipeline or other object under the wooden mats may be damaged by a heavy vehicle.
US patent application publication no. 2013/0047351 describes a pipeline crossing bridge. The arch-shaped bridge is of a fixed size and is constructed to be one piece that is placed over a pipeline.
U.S. design Pat. No. 763,414 shows a fluid line drive over. It is one piece having a smooth top surface and includes pipes extending through the interior of the structure. This design patent does not describe supporting feet to raise the structure above a ground surface.
U.S. Pat. No. 8,955,184 describes a bridge comprising multiple bridge elements configured to be superimposed when the bridge is in a first non-deployed position. The bridge elements are initially vertically stacked and each two successive bridge elements are connected using a pair of parallel coupling arms positioned at the sides of the bridge elements. The coupling arms are used to articulate the bridge elements outwards to form a bridge that spans across a gap. The bridge elements can be removed from the stack to vary the length of bridge. This patent does not describe supporting feet to raise the bridge above a ground surface.
U.S. Pat. No. 3,768,108 describes an arched bridge that includes a pair of arched longitudinal opposite side structural members interconnected by crossed diagonal bracing members secured there-between by bolting. This bridge is intended to be of a fixed size. Furthermore, while this bridge is intended to be shipped disassembled and assembled on site, the assembly is time consuming as there are many parts.
U.S. Pat. No. 5,603,134 describes a portable bridge system formed from at least a pair of rectangular bridge platforms positioned in side-by-side relationship including end locking plates for locking the platforms together at the end regions thereof.
US patent application publication no. 2013/0284872 describes a pipeline mat. While this pipeline mat is constructed as one piece, the pipeline mat includes a slidably replaceable top layer material, such as wood planks, for repair purposes. Each wood plank is cut to a finished dimension with L-shaped notches at its ends in order to slide beneath the metal frame. This patent application does not describe supporting feet to raise the mat.